TNF and systemic sclerosis: In addition to the IL-17 family, other TH17-derived cytokine members also have clear correlations with SSc, one of which is the production and secretion of IL-22, a crucial pro-inflammatory cytokine in the skin because of its increased ability to destroy bacteria and produce chemokines, such as IL-8 and MCP-1, as well as cytokines TNF, IL-1, and IL-12 [129].